From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- drivers/rtc/rtc-mpc5121.c | 408 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 408 insertions(+) create mode 100644 drivers/rtc/rtc-mpc5121.c (limited to 'drivers/rtc/rtc-mpc5121.c') diff --git a/drivers/rtc/rtc-mpc5121.c b/drivers/rtc/rtc-mpc5121.c new file mode 100644 index 000000000..b90f8337a --- /dev/null +++ b/drivers/rtc/rtc-mpc5121.c @@ -0,0 +1,408 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Real-time clock driver for MPC5121 + * + * Copyright 2007, Domen Puncer + * Copyright 2008, Freescale Semiconductor, Inc. All rights reserved. + * Copyright 2011, Dmitry Eremin-Solenikov + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +struct mpc5121_rtc_regs { + u8 set_time; /* RTC + 0x00 */ + u8 hour_set; /* RTC + 0x01 */ + u8 minute_set; /* RTC + 0x02 */ + u8 second_set; /* RTC + 0x03 */ + + u8 set_date; /* RTC + 0x04 */ + u8 month_set; /* RTC + 0x05 */ + u8 weekday_set; /* RTC + 0x06 */ + u8 date_set; /* RTC + 0x07 */ + + u8 write_sw; /* RTC + 0x08 */ + u8 sw_set; /* RTC + 0x09 */ + u16 year_set; /* RTC + 0x0a */ + + u8 alm_enable; /* RTC + 0x0c */ + u8 alm_hour_set; /* RTC + 0x0d */ + u8 alm_min_set; /* RTC + 0x0e */ + u8 int_enable; /* RTC + 0x0f */ + + u8 reserved1; + u8 hour; /* RTC + 0x11 */ + u8 minute; /* RTC + 0x12 */ + u8 second; /* RTC + 0x13 */ + + u8 month; /* RTC + 0x14 */ + u8 wday_mday; /* RTC + 0x15 */ + u16 year; /* RTC + 0x16 */ + + u8 int_alm; /* RTC + 0x18 */ + u8 int_sw; /* RTC + 0x19 */ + u8 alm_status; /* RTC + 0x1a */ + u8 sw_minute; /* RTC + 0x1b */ + + u8 bus_error_1; /* RTC + 0x1c */ + u8 int_day; /* RTC + 0x1d */ + u8 int_min; /* RTC + 0x1e */ + u8 int_sec; /* RTC + 0x1f */ + + /* + * target_time: + * intended to be used for hibernation but hibernation + * does not work on silicon rev 1.5 so use it for non-volatile + * storage of offset between the actual_time register and linux + * time + */ + u32 target_time; /* RTC + 0x20 */ + /* + * actual_time: + * readonly time since VBAT_RTC was last connected + */ + u32 actual_time; /* RTC + 0x24 */ + u32 keep_alive; /* RTC + 0x28 */ +}; + +struct mpc5121_rtc_data { + unsigned irq; + unsigned irq_periodic; + struct mpc5121_rtc_regs __iomem *regs; + struct rtc_device *rtc; + struct rtc_wkalrm wkalarm; +}; + +/* + * Update second/minute/hour registers. + * + * This is just so alarm will work. + */ +static void mpc5121_rtc_update_smh(struct mpc5121_rtc_regs __iomem *regs, + struct rtc_time *tm) +{ + out_8(®s->second_set, tm->tm_sec); + out_8(®s->minute_set, tm->tm_min); + out_8(®s->hour_set, tm->tm_hour); + + /* set time sequence */ + out_8(®s->set_time, 0x1); + out_8(®s->set_time, 0x3); + out_8(®s->set_time, 0x1); + out_8(®s->set_time, 0x0); +} + +static int mpc5121_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); + struct mpc5121_rtc_regs __iomem *regs = rtc->regs; + unsigned long now; + + /* + * linux time is actual_time plus the offset saved in target_time + */ + now = in_be32(®s->actual_time) + in_be32(®s->target_time); + + rtc_time64_to_tm(now, tm); + + /* + * update second minute hour registers + * so alarms will work + */ + mpc5121_rtc_update_smh(regs, tm); + + return 0; +} + +static int mpc5121_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); + struct mpc5121_rtc_regs __iomem *regs = rtc->regs; + unsigned long now; + + /* + * The actual_time register is read only so we write the offset + * between it and linux time to the target_time register. + */ + now = rtc_tm_to_time64(tm); + out_be32(®s->target_time, now - in_be32(®s->actual_time)); + + /* + * update second minute hour registers + * so alarms will work + */ + mpc5121_rtc_update_smh(regs, tm); + + return 0; +} + +static int mpc5200_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); + struct mpc5121_rtc_regs __iomem *regs = rtc->regs; + int tmp; + + tm->tm_sec = in_8(®s->second); + tm->tm_min = in_8(®s->minute); + + /* 12 hour format? */ + if (in_8(®s->hour) & 0x20) + tm->tm_hour = (in_8(®s->hour) >> 1) + + (in_8(®s->hour) & 1 ? 12 : 0); + else + tm->tm_hour = in_8(®s->hour); + + tmp = in_8(®s->wday_mday); + tm->tm_mday = tmp & 0x1f; + tm->tm_mon = in_8(®s->month) - 1; + tm->tm_year = in_be16(®s->year) - 1900; + tm->tm_wday = (tmp >> 5) % 7; + tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); + tm->tm_isdst = 0; + + return 0; +} + +static int mpc5200_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); + struct mpc5121_rtc_regs __iomem *regs = rtc->regs; + + mpc5121_rtc_update_smh(regs, tm); + + /* date */ + out_8(®s->month_set, tm->tm_mon + 1); + out_8(®s->weekday_set, tm->tm_wday ? tm->tm_wday : 7); + out_8(®s->date_set, tm->tm_mday); + out_be16(®s->year_set, tm->tm_year + 1900); + + /* set date sequence */ + out_8(®s->set_date, 0x1); + out_8(®s->set_date, 0x3); + out_8(®s->set_date, 0x1); + out_8(®s->set_date, 0x0); + + return 0; +} + +static int mpc5121_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); + struct mpc5121_rtc_regs __iomem *regs = rtc->regs; + + *alarm = rtc->wkalarm; + + alarm->pending = in_8(®s->alm_status); + + return 0; +} + +static int mpc5121_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); + struct mpc5121_rtc_regs __iomem *regs = rtc->regs; + + alarm->time.tm_mday = -1; + alarm->time.tm_mon = -1; + alarm->time.tm_year = -1; + + out_8(®s->alm_min_set, alarm->time.tm_min); + out_8(®s->alm_hour_set, alarm->time.tm_hour); + + out_8(®s->alm_enable, alarm->enabled); + + rtc->wkalarm = *alarm; + return 0; +} + +static irqreturn_t mpc5121_rtc_handler(int irq, void *dev) +{ + struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev); + struct mpc5121_rtc_regs __iomem *regs = rtc->regs; + + if (in_8(®s->int_alm)) { + /* acknowledge and clear status */ + out_8(®s->int_alm, 1); + out_8(®s->alm_status, 1); + + rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static irqreturn_t mpc5121_rtc_handler_upd(int irq, void *dev) +{ + struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev); + struct mpc5121_rtc_regs __iomem *regs = rtc->regs; + + if (in_8(®s->int_sec) && (in_8(®s->int_enable) & 0x1)) { + /* acknowledge */ + out_8(®s->int_sec, 1); + + rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_UF); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static int mpc5121_rtc_alarm_irq_enable(struct device *dev, + unsigned int enabled) +{ + struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); + struct mpc5121_rtc_regs __iomem *regs = rtc->regs; + int val; + + if (enabled) + val = 1; + else + val = 0; + + out_8(®s->alm_enable, val); + rtc->wkalarm.enabled = val; + + return 0; +} + +static const struct rtc_class_ops mpc5121_rtc_ops = { + .read_time = mpc5121_rtc_read_time, + .set_time = mpc5121_rtc_set_time, + .read_alarm = mpc5121_rtc_read_alarm, + .set_alarm = mpc5121_rtc_set_alarm, + .alarm_irq_enable = mpc5121_rtc_alarm_irq_enable, +}; + +static const struct rtc_class_ops mpc5200_rtc_ops = { + .read_time = mpc5200_rtc_read_time, + .set_time = mpc5200_rtc_set_time, + .read_alarm = mpc5121_rtc_read_alarm, + .set_alarm = mpc5121_rtc_set_alarm, + .alarm_irq_enable = mpc5121_rtc_alarm_irq_enable, +}; + +static int mpc5121_rtc_probe(struct platform_device *op) +{ + struct mpc5121_rtc_data *rtc; + int err = 0; + + rtc = devm_kzalloc(&op->dev, sizeof(*rtc), GFP_KERNEL); + if (!rtc) + return -ENOMEM; + + rtc->regs = devm_platform_ioremap_resource(op, 0); + if (IS_ERR(rtc->regs)) { + dev_err(&op->dev, "%s: couldn't map io space\n", __func__); + return PTR_ERR(rtc->regs); + } + + device_init_wakeup(&op->dev, true); + + platform_set_drvdata(op, rtc); + + rtc->irq = irq_of_parse_and_map(op->dev.of_node, 1); + err = devm_request_irq(&op->dev, rtc->irq, mpc5121_rtc_handler, 0, + "mpc5121-rtc", &op->dev); + if (err) { + dev_err(&op->dev, "%s: could not request irq: %i\n", + __func__, rtc->irq); + goto out_dispose; + } + + rtc->irq_periodic = irq_of_parse_and_map(op->dev.of_node, 0); + err = devm_request_irq(&op->dev, rtc->irq_periodic, + mpc5121_rtc_handler_upd, 0, "mpc5121-rtc_upd", + &op->dev); + if (err) { + dev_err(&op->dev, "%s: could not request irq: %i\n", + __func__, rtc->irq_periodic); + goto out_dispose2; + } + + rtc->rtc = devm_rtc_allocate_device(&op->dev); + if (IS_ERR(rtc->rtc)) { + err = PTR_ERR(rtc->rtc); + goto out_dispose2; + } + + rtc->rtc->ops = &mpc5200_rtc_ops; + set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->rtc->features); + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->rtc->features); + rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_0000; + rtc->rtc->range_max = 65733206399ULL; /* 4052-12-31 23:59:59 */ + + if (of_device_is_compatible(op->dev.of_node, "fsl,mpc5121-rtc")) { + u32 ka; + ka = in_be32(&rtc->regs->keep_alive); + if (ka & 0x02) { + dev_warn(&op->dev, + "mpc5121-rtc: Battery or oscillator failure!\n"); + out_be32(&rtc->regs->keep_alive, ka); + } + rtc->rtc->ops = &mpc5121_rtc_ops; + /* + * This is a limitation of the driver that abuses the target + * time register, the actual maximum year for the mpc5121 is + * also 4052. + */ + rtc->rtc->range_min = 0; + rtc->rtc->range_max = U32_MAX; + } + + err = devm_rtc_register_device(rtc->rtc); + if (err) + goto out_dispose2; + + return 0; + +out_dispose2: + irq_dispose_mapping(rtc->irq_periodic); +out_dispose: + irq_dispose_mapping(rtc->irq); + + return err; +} + +static void mpc5121_rtc_remove(struct platform_device *op) +{ + struct mpc5121_rtc_data *rtc = platform_get_drvdata(op); + struct mpc5121_rtc_regs __iomem *regs = rtc->regs; + + /* disable interrupt, so there are no nasty surprises */ + out_8(®s->alm_enable, 0); + out_8(®s->int_enable, in_8(®s->int_enable) & ~0x1); + + irq_dispose_mapping(rtc->irq); + irq_dispose_mapping(rtc->irq_periodic); +} + +#ifdef CONFIG_OF +static const struct of_device_id mpc5121_rtc_match[] = { + { .compatible = "fsl,mpc5121-rtc", }, + { .compatible = "fsl,mpc5200-rtc", }, + {}, +}; +MODULE_DEVICE_TABLE(of, mpc5121_rtc_match); +#endif + +static struct platform_driver mpc5121_rtc_driver = { + .driver = { + .name = "mpc5121-rtc", + .of_match_table = of_match_ptr(mpc5121_rtc_match), + }, + .probe = mpc5121_rtc_probe, + .remove = mpc5121_rtc_remove, +}; + +module_platform_driver(mpc5121_rtc_driver); + +MODULE_DESCRIPTION("Freescale MPC5121 built-in RTC driver"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("John Rigby "); -- cgit v1.3.1